The disclosure relates generally to support structures, and more particularly, to support structures for rotors of industrial machines.
In conventional power or turbine systems, a rotor of the system is typically supported adjacent to or at one or both ends of the rotor. The rotor may be supported by a number of structures or housings that help to maintain the rotor within the system. Specifically, a portion or end(s) of the rotor may be positioned within and supported by these conventional structures or housings during operation of the turbine system. Additionally, these structures or housings are configured to allow the rotor to freely spin within the system and in the structure or housing. To help support and stabilize the rotor and the structure of the turbine system, conventional structures or housings are typically coupled to a stationary enclosure surrounding the rotor of the turbine system.
During operation of conventional turbine systems, the components or parts of the system heat-up. As a result, some of these components undergo thermal expansion. To compensate for the thermal expansion of these components, other portions of the turbine system must be designed to move and/or flex. For example, to compensate for the thermal expansion of the rotor and/or the enclosure surrounding the rotor, the structure or housing supporting the rotor may be designed to move (e.g., axially). In conventional systems, the movement of structure or housing supporting the rotor may be controlled by flex legs, typically formed by thin and flexible metal plates. The flex legs may be fixed to and support the structure or housing. These flex legs may bend, flex and/or deflect to allow the structure or housing supporting the rotor to move with the thermally expanding enclosure and/or rotor.
However, the use of the flex legs within the turbine system may present other issues or problems during operation. For example, the rotor of the turbine system may spin at high-speeds during operation. Because of the flexible characteristics of the flex legs and the resulting movement of the structure or housing supporting the rotor, the rotor spinning at high-speeds may also experience high vibrations. The vibrations may increase as the operational speed of the rotor increases. The vibration of the rotor may decrease the efficiency and/or operational performance of the rotor and ultimately the turbine system. Additionally as the vibrations of the rotor increases, the flex legs may become excited and eventually begin to vibrate or flutter (e.g., harmonic motion) as well. The fluttering of the flex legs often “trips” the turbine system due to excessive vibration of the rotor, which causes the system to shut down. As a result, to avoid tripping the turbine system, the rotor may be required to operate at less than full speed, which means the turbine system is operating at a reduced capacity. Furthermore, increasing the size, thickness and/or number of flex legs may help to reduce the vibration of the rotor, but typically is not feasible due to the clearance space within the turbine system and/or the thermal expansion of the various components of the turbine system.